• George Wort's avatar
    Revert "[turbofan][arm64] Emit Lsl for Int32MulWithOverflow when possible" · f0664528
    George Wort authored
    This reverts commit aa541f1c.
    
    Reason for revert: Reverting due to large regressions for motionmark on M1.
    
    Original change's description:
    > [turbofan][arm64] Emit Lsl for Int32MulWithOverflow when possible
    >
    > Int32MulWithOverflow on arm64 uses a cmp to set flags rather than
    > the multiply instruction itself, thus we can use a left shift when
    > the multiplication is by a power of two.
    >
    > This provides 0.15% for Speedometer2 on a Neoverse-N1 machine,
    > with React being improved by 0.45%.
    >
    > Change-Id: Ic8db42ecc7cb14cf1ac7bbbeab0e9d8359104351
    > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3829472
    > Commit-Queue: George Wort <george.wort@arm.com>
    > Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
    > Cr-Commit-Position: refs/heads/main@{#82499}
    
    Change-Id: I896530a53fbdf6d397922124abddda4140144448
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3854222Reviewed-by: 's avatarNico Hartmann <nicohartmann@chromium.org>
    Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
    Commit-Queue: George Wort <george.wort@arm.com>
    Cr-Commit-Position: refs/heads/main@{#82696}
    f0664528
instruction-selector-arm64.cc 170 KB